I have been attempting to do a fresh install of Discourse on a fresh installation of Ubuntu Server 16.04 but the installation fails during bootstrapping.
The launcher downloads the Discourse image successfully but fails when attempting to access ‘GitHub - discourse/pups: Simple yaml based bootstrapper for Linux machines’ with the following error.
fatal: unable to access ‘GitHub - discourse/pups: Simple yaml based bootstrapper for Linux machines’: gnutls_handshake() failed: Error in the pull function.
I have uncommented DOCKER_OPTS in /etc/default/docker so docker uses googles DNS but this didnt fix the issue.
I checked with my server host to see if anything was being blocked on their end that would cause this, i was told no. They did however mention that the docker0 interface using an MTU of 1500 instead of their recommended 1400 may be causing the issue. I have noticed that the Veth interface that appears only during the bootstrapping process also uses an MTU of 1500.
Can anyone confirm that the MTU may cause this issue? I have attempted to change the MTU that docker uses but havent had any luck, i added --mtu=1400 to the DOCKER_OPTS but this doesnt appear to change anything. Am i changing the MTU in the wrong location?
Its entirely possible that my server host was mistaken and there is indeed something on their network causing this issue but id like to first rule out the MTU before i contact them again.
Does anyone have any suggestions? Im happy to provide some more information if requested.